BAND-STRUCTURE AND MANY-BODY EFFECTS IN THE DYNAMICAL RESPONSE OF ALUMINUM METAL

For many years, efforts to explain a double peak observed in the dynamical structure factor S(q; of aluminum an archetype of jellium electronic behavior via inelastic x-ray scattering have concentrated on many-body mechanisms for the uniform electron liquid. On the basis of a first-principles evaluation of S(q; ) for Al crystal we show that the double peak is an intrinsic feature of the response of noninteracting electron-hole pairs. Many-electron effects, in the form of a vertex correction for the irreducible polarizability, are found to substantially improve the agreement with experiment of the calculated loss intensities. © 1995 The American Physical Society.